Fix external tmux command without display

alot/commands/globals.py

@@ -221,7 +221,7 @@ def __init__(self, cmd, stdin=None, shell=False, spawn=False,
             logging.debug('calling hook: touch_external_cmdlist')
             res = touchhook(cmd, shell=shell, spawn=spawn, thread=thread)
             logging.debug('got: %s', res)
-            cmd, shell, self.in_thread = res
+            cmd, shell, thread = res
         # otherwise if spawn requested and X11 is running
         elif spawn:
             if 'DISPLAY' in os.environ:
@@ -230,6 +230,7 @@ def __init__(self, cmd, stdin=None, shell=False, spawn=False,
                 termcmdlist = split_commandstring(term_cmd)
                 cmd = termcmdlist + cmd
             else:
+                logging.warning('unable to handle spawn outside of X11 without touch_external_cmdlist hook set')
                 thread = False
 
         self.cmdlist = cmd

extra/hooks/external_command_tmux_without_x11.py

@@ -0,0 +1,12 @@
+import os
+
+
+def touch_external_cmdlist(cmd, shell=False, spawn=False, thread=False):
+    # Used to handle the case where tmux isn't running within X11
+    if spawn and 'TMUX' in os.environ:
+        termcmdlist = ['tmux-horizontal-split-blocking.sh']
+        cmd = termcmdlist + cmd
+        # Required to avoid tmux trying to nest itself.
+        shell = False
+
+    return cmd, shell, thread

extra/tmux-horizontal-split-blocking.sh

@@ -0,0 +1,17 @@
+#!/bin/sh
+# Uses unique tmux wait-for channel based on time with nanoseconds
+# Inspired by cjpbirkbeck's example @ https://github.com/pazz/alot/issues/1560#issuecomment-907222165
+
+IFS=' '
+
+# Ensure we're actually running inside tmux:
+if [ -n "$TMUX" ]; then
+    fin=$(date +%s%N)
+    # Use new-window to create a new window instead.
+    tmux split-window -h "${*}; tmux wait-for -S ${fin}"
+    tmux wait-for "${fin}"
+else
+    # You can replace xterm with your preferred terminal emulator.
+    xterm -e "${*}"
+fi
+